1. Field of the Invention
The present invention relates to a power-charging system for a transporter cart, and more particularly to a power-charging system of this type for charging an electric-powered transporter cart which mounts a battery for automatically propelling the transporter cart along a predetermined travelling route.
2. Description of the Related Art
In this type of power-charging system, a power-charging operation to the transporter cart is generally done at a power-charging station specially provided for the system, since the power-charge requires a long period of time. According to another conventional method, an exhausted battery is dismounted from the transporter cart for replacement with a newly charged battery.
In the former case, the transporter cart remains out of service for e.g. transporting job while the cart stays at the power-charging station. In the latter case, the replacement of the batteries is time-consuming and troublesome. In either case, the entire transport system suffers inefficiency.
For improvement of the system efficiency, it is essential to maximize the interval between power-charging operations by minimizing power consumption of the battery. Conventionally, this is done by specially designing the transporter cart for improvement of power consumption economy or by effecting an auxiliary power-charging operation to the transporter cart in the middle of its transporting job.
The power-charging operation at the station is generally done while the transporter cart is stopped for mounting or dismounting load to or from the cart. In other words, the time period available for power-charging operation is limited by the time period required of the load mounting/dismounting work. Thus, the system suffers significant inefficiency if the cart is stopped at the station only for power charge after the job is done.
The present invention attends to these inconveniences of the convention. The primary object of the present invention is to provide an improved power-charging system for a transporter cart, which system can efficiently charge the cart without sacrificing efficiency of the entire transport system while minimizing power consumption of this transporter cart.